Tab locks, used in mailboxes, lockers, or closets, are usually mechanical, that is to say, they require the use of a key for its opening and closing.
Electronic cylinders that open the door in electronic locks are not used in this type of mechanical locks, given that the operation of these electronic cylinders is based on a rotor that rotates freely until its activation, when the rotor engages a drive cam which, after being engaged, rotates together with the rotor and opens the door. Said cam is free until the drive cam is engaged, which in those door locks where the cam is inside the door presents no problems, given that it cannot be easily manipulated from the outside.
The reason for not using electronic cylinder mechanisms in tab locks is that, in these locks, the cam is the tab itself, and this tab is easily accessible for its manipulation (by means of x-rays, for example); therefore, given that the tab is unlocked, manipulating the tab and opening the lock without a key would be very simple.